Fine Tuner - Fine Tuner is a minimalistic guitar tuner that utilizes your device's built-in microphone.
guitarLayers - guitarLayers is a professional macOS guitar learning software.
Metronomus - Powerful and beautiful online metronome
Fachords - Fachords is an online site that provides many resources that you can use to take your guitar skills to the next level.
LINGOT - Musical instrument tuner, LINGOT is a musical instrument tuner.
TrueFire - The Best Guitar Lessons Online Fast. Easy. Fun.